When Thought Becomes a Trap: Rumination, Attentional Rigidity, and Suicidal Vulnerability in Depression - An Integrative Clinical-Neurocognitive Review and EEG-Informed Research Framework for Psychotherapeutic Change

Rumination is often described as excessive thinking, but this description misses the clinical problem: some thoughts become difficult to leave even when they no longer help a person act. This article integrates clinical psychology, cognitive neuropsychology, affective neuroscience, psychophysiology, and suicide prevention to ask whether depression-related rumination reflects a context-dependent failure to disengage from self-referential negative information, how such processing might be observed with electroencephalography (EEG), and whether psychotherapy can alter it. Evidence from cognitive-control meta-analyses supports a selective association between repetitive negative thinking and difficulties removing irrelevant material from working memory, rather than a uniform executive deficit. EEG event-related potentials offer temporally precise, but non-diagnostic, measures of attention, motivational salience, and performance monitoring. Rumination is associated with suicidal ideation; nevertheless, ideation, attempts, and suicide death are distinct outcomes, and association does not establish mechanism. Psychotherapy can reduce depressive symptoms and suicidal outcomes in selected contexts, while evidence that EEG change mediates clinical benefit remains limited. I propose a falsifiable contextual disengagement framework and a staged research programme combining interviews, longitudinal symptom assessment, ecological momentary assessment, cognitive tasks, preregistered EEG analysis, and a controlled psychotherapy study. Alternative explanations, measurement artifacts, confounding, cultural variation, publication bias, and participant safety are treated as substantive challenges rather than footnotes. The article is a targeted, critical narrative synthesis and research proposal. It reports no newly collected participants, EEG recordings, clinical trial outcomes, or causal treatment effects.